Glass article and method for producing the same

Abstract

A method for producing a glass article is provided. The method for producing a glass article, the method including preparing a glass to be processed, the glass comprising a glass bulk and a low-refractive surface layer disposed on the glass bulk, and etching away the low-refractive surface layer to form an etched glass, wherein the etching away the low-refractive surface layer comprises: cleaning the low-refractive surface layer with an acid solution; and cleaning the low-refractive surface layer with a base solution after the cleaning it with the acid solution.

What is claimed is: 
     
       1. A method for producing a glass article, the method comprising:
 preparing a glass to be processed, 
 strengthening the glass by ion exchange process so that the glass becomes a strengthened glass and includes a first portion and a second portion disposed on the first portion, wherein the strengthening the glass is performed without using any acid solution and under a condition that a ratio of a silicon content of the second portion to a silicon content of the first portion of the strengthened glass becomes between 1.2 and 1.4 and a thickness of the second portion becomes a first thickness after the strengthening the glass; and 
 etching away the second portion to form an etched glass, 
 wherein the etching away the second portion comprises:
 applying the second portion with an acid solution, wherein the thickness of the second portion becomes a second thickness which is not greater than the first thickness after the applying the second portion with the acid solution; and 
 applying the second portion with a base solution such that the thickness of the second portion becomes smaller than the second thickness after applying the second portion with the base solution, and 
 
 wherein the applying the second portion with the acid solution includes transforming the second portion into a state that is removed by a base cleaning process using the base solution. 
 
     
     
       2. The method of  claim 1 , wherein the cleaning with the acid solution is carried out for 0.5 to 5 minutes using an acidic solution containing nitric acid in an amount between 2 wt % and 5 wt %, and
 wherein the cleaning with the base solution is carried out for 0.5 to 5 minutes using a base solution containing sodium hydroxide in an amount between 2 wt % and 5 wt %. 
 
     
     
       3. The method of  claim 2 , wherein the second portion is not removed during the applying with the acid solution, and is removed during the applying with the base solution. 
     
     
       4. The method of  claim 1 , wherein a thickness of the second portion of the glass ranges from 100 to 500 nm. 
     
     
       5. The method of  claim 4 , wherein the etching away the second portion to form the etched glass comprises removing the second portion completely. 
     
     
       6. The method of  claim 1 , wherein the thickness of the second portion is less than 100 nm after the etching away the second portion to form an etched glass. 
     
     
       7. The method of  claim 1 , wherein the glass comprises a compressive region disposed adjacent to a surface thereof and a tensile region disposed inside of the compressive region,
 wherein the second portion is disposed in the compressive region, and 
 wherein a thickness of the second portion is smaller than a compression depth of the compressive region. 
 
     
     
       8. The method of  claim 7 , wherein a maximum compressive stress of the etched glass is less than a maximum compressive stress of the glass. 
     
     
       9. The method of  claim 8 , wherein a difference between the maximum compressive stress of the glass and the maximum compressive stress of the etched glass ranges from 10 MPa to 100 MPa. 
     
     
       10. The method of  claim 7 , wherein a compression depth of the etched glass is equal to the compression depth of the glass. 
     
     
       11. The method of  claim 7 , wherein a maximum tensile stress (CT 1 ) of the etched glass satisfies
   CT1≥−37.6*ln( t )+48.7,
 
 where CT 1  is expressed in MPa, and t denotes the thickness of the etched glass in mm. 
 
     
     
       12. The method of  claim 11 , wherein a maximum tensile stress of the glass satisfies
   CT1′>−37.6*ln( t ′)+48.7,
 
 where CT 1 ′ is expressed in MPa, and t′ denotes the thickness of the glass in mm. 
 
     
     
       13. The method of  claim 7 , wherein the compressive region has a maximum compressive stress at a surface of the second portion. 
     
     
       14. The method of  claim 1 , wherein a refractive index of the second portion is smaller than a refractive index of the first portion and is greater than a refractive index of air.